Apparently according to this article:
http://biz.yahoo.com/bw/990908/ca_corners_1.html
There is a new building being built at 3do. Possibly for a new online project?

"SAN FRANCISCO--(BUSINESS WIRE)--Sept. 8, 1999--Cornerstone Properties Inc. (NYSE:CPP - news) announced today that it has signed a long term lease with The 3DO Company (NASDAQ:THDO - news) for the entire 160,000 square foot office development project at Seaport Plaza in Redwood City, California. The 3DO Company develops, publishes and markets interactive entertainment for multiple platforms including the PC, PlayStation® game console, Nintendo® 64, and the Internet."

Source: m59-dungeon.com